HDPE增韧PP-R/石墨复合材料力学性能的研究

采用高密度聚乙烯(HDPE)为增韧剂、乙烯 丙烯 二烯三元共聚物(EPDM)、乙烯 辛烯共聚物(POE)为相容剂、石墨为功能性助剂制备了以无规共聚聚丙烯(PP R)或嵌段共聚聚丙烯(PP B)为基体的PP R或PP B／HDPE／石墨复合材料。详细研究了HDPE含量、弹性体种类及含量对PP R或PP B／HDPE／石墨复合材料力学性能的影响。结果表明HDPE用量在20%、EPDM含量为5%时,PP R或PP B复合材料力学性能优异;POE可以实现PP R或PP B／HDPE／石墨复合材料力学性能的平衡。     

PP/EPDM/滑石粉复合材料的抗冲击性能以及添加PE-双嵌段共聚物的效果

研究了添加低密度聚乙烯嵌段-聚丙烯酸酯共聚物（PE-双嵌段）对含有乙烯-丙烯-二烯烃三元共聚物（EPDM）和滑石粉的聚丙烯（PP）三元复合材料冲击强度的影响。滑石粉表面用γ-环氧丙氧基三甲基硅烷（GPMS）进行处理,以增强滑石粉表面与所添加共聚物羧基官能团之间的相互作用。复合材料用双螺杆挤出机制备,当PE-双嵌段的含量达到3wt％时,PP／EPDM（5wt％）／滑石（30wt％）粉复合材料的;中击强度显著增加,大约可提高40％。     

相容剂对稻糠/聚丙烯复合材料加工性能和尺寸稳定性的影响

通过反应挤出法制备了马来酸酐接枝乙烯-辛烯共聚物(POE-g-MAH)相容剂,研究了POE-g-MAH对稻糠/聚丙烯(PP)复合材料力学性能、加工性能和尺寸稳定性的影响。结果表明:POE-g-MAH增容效果优于马来酸酐接枝三元乙丙橡胶(EPDM-g-MAH)和马来酸酐接枝聚丙烯(PP-g-MAH),能显著提高复合材料的拉伸强度、冲击强度、弯曲强度和尺寸稳定性;EPDM-g-MAH和PP-g-MAH对复合材料加工性能影响不大,而POE-g-MAH使稻糠/PP复合材料的最大转矩和平衡转矩明显降低,加工性能得到改善。     

增韧增强PP复合材料的研究

研究了聚丙烯(PP)种类,增韧剂丙烯-辛烯共聚物、苯乙烯-丁二烯-苯乙烯嵌段共聚物,三元乙丙橡胶(SBS／EPDM)和CaCO3用量对PP复合材料性能的影响。结果表明：以PP EPF30M为基体树脂,SBS／EPDM为增韧剂,CaCO3为增强剂。当添加SBS／EPDM质量分数为25％,CaCO3质量分数为19％时,制得的增韧增强PP复合材料满足PP汽车保险杠专用料的要求。     

PP/HDPE/弹性体三元共混改性的研究

用双螺杆挤出机制备了聚丙烯(PP)/高密度聚乙烯(HDPE)/弹性体三元共混物,分别探讨了3种弹性体乙烯-辛烯嵌段共聚物(OBC)、苯乙烯-丁二烯-苯乙烯嵌段共聚物(SBS)、苯乙烯-乙烯/丁烯-苯乙烯嵌段共聚物(SEBS)的含量对PP三元共混物力学性能的影响,并通过扫描电子显微镜观察其脆断表面形态。结果表明,OBC、SBS、SEBS和HDPE都对PP起到了一定的协同增韧作用,SEBS对PP的增韧效果最佳;SEM表明三元共混力学性能与相形态密切相关;所制备的PP/HDPE/OBC三元共混物的加工性能较好。     

新的汽车保险杠用树脂

日本的日产汽车公司与三菱油化公司协作,共同开发在功了以聚丙烯为基础的汽车保险杠用树脂。 这种新开发的树脂由聚丙烯嵌段共聚物、苯乙烯系弹性体和烯烃系乙丙橡胶三种成份配合而,这三种成份相辅相成,可保证保险杠所必须具有的特性,即刚性、耐冲击性、耐擦伤性、光泽、弹性、可涂装性等。 因此,用这种树脂制成的保险杠具有即使经时速80公里的速度冲撞后也能恢复原状的特性,并且这种树脂加工性能良好,可以注     

汽车外装用聚丙烯改性料的研制

由于以适量高流动性丙烯－乙烯嵌段共聚物，乙丙共聚系橡胶，马来酸酐接枝改性聚丙烯，高密度聚乙烯，微细滑石粉为主要成分的聚丙烯改性料，在具有优异成型性的同时，兼有硬度不降低，而且耐冲击性提高，延伸性，机械强度及尺寸稳定等综合性能良好，很适用于汽车保险杠等外装制品，而且制品涂饰性也优异。     

组分对PA6/PP/滑石粉三元复合材料的影响

通过双螺杆挤出制备了尼龙6(PA6)/聚丙烯(PP)/滑石粉三元复合材料,考察不同PA6、PP及滑石粉和增容剂种类及含量对PA6/PP/滑石粉三元复合材料力学性能的影响。结果表明,中黏度(2.4~2.7 Pa·s)PA6、聚乙烯(PE)含量达到7%~9%的嵌段共聚PP及粒径为2~5μm的滑石粉制备的PA/PP/滑石粉三元复合材料具有优异的力学性能;随着PA6含量增加,PA6/PP/滑石粉三元复合材料的拉伸、弯曲强度增加,吸水率上升,PP含量增加,PA6/PP/滑石粉三元复合材料吸水率下降,拉伸强度和弯曲强度也下降;滑石粉的粒径越大,PA6/PP/滑石粉三元复合材料的刚性越好,冲击强度越差,滑石粉的粒径越小,则容易团聚,三元复合材料形成应力集中点;增容剂马来酸酐接枝乙烯-醋酸乙烯酯共聚物(EVAC-g-MAH)和马来酸酐接枝三元乙丙橡胶(EPDM-g-MAH)复配对PA6/PP/滑石粉三元复合材料增容效果优于马来酸酐接枝聚丙烯(PP-g-MAH)或EPDM-g-MAH;当EVAC-gMAH和EPDM-g-MAH添加量各为5%,PA6/PP/滑石粉质量比为50/20/20时,制备出的PA6/PP/滑石粉三元复合材料具有较佳的力学性能,并有优异的加工性能,其缺口冲击强度可达6.6 k J/m^2。     

聚丙烯基树脂组合物用于汽车零部件、汽车外饰件

正提供了一种聚丙烯基树脂组合物具有优异的成型性,适用于具有高刚性零件的成型,优良的表面外观和良好的表面的冲击性,特别是汽车保险杠。该组合物包括:(30~62)wt%的丙烯共聚物具有(40~70)g/10min MFR;5基于嵌段共聚物包括高MFR结晶聚丙烯段和特定的乙烯-丙烯共聚物段和具有(100~130)g/10min MFR丙烯20wt%;10催%的组合的两个乙烯-α-烯烃共聚物弹性体都有一个特定的MFR和密度;(23~30)wt%具有特定粒     

聚丙烯／碳酸钙复合材料研究的新进展

清华大学日前在研究高填充增韧聚丙烯 /碳酸钙复合材料方面取得突破性进展 ,不仅可实现刚性粒子增韧工业化 ,而且可显著降低聚丙烯 /碳酸钙复合材料的生产成本。高填充增韧聚丙烯 /碳酸钙复合材料技术可实现对聚丙烯的高填充和增韧 ,达到在改性的同时降低材料成本的目的。在 5 0 %～ 6 0 %的碳酸钙高填充量下 ,其韧性也能提高 1倍左右 ,而且拉伸强度降低幅度不超过一般复合技术在同等填充量时的水准。该技术是按汽车保险杠要求的材料标准设计的。一般汽车保险杠用材料是以添加 2 0 %～ 2 5 %三元乙丙胶价格高 ,所以汽车保险杠用材料成本也相…     

Polymeric proton conducting systems based on commercial elastomers. II. Synthesis and microstructural characterization of films based on HSBR/EPDM/PP/PS/silica

This article reports on the synthesis and structural characterization of films containing hydrogenated poly(butadiene‐styrene) block copolymer/ethylene‐propylene terpolymer/polypropylene, hydrogenated poly(butadiene‐styrene) block copolymer/ethylene‐propylene terpolymer/polystyrene, and hydrogenated poly(butadiene‐styrene block copolymer/ethylene‐propylene terpolymer/silica) crosslinked with peroxides and heterogeneously sulfonated. Sulfonation of the different polymeric systems gives rise to materials with high proton conductivity and great dimensional stability, suited for application in a variety of electronic devices. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 2394–2402, 2004     

Preparation of composites based on recycled polypropylene and automotive shredder residue

In past research, mechanical recycling of automotive shredder residue (ASR) has led to serious deterioration of material performance, and real‐scale application in this way still remains a challenge. Here, we report a sustainable approach called solid‐state shear milling (SSSM) for the production of high‐performance polypropylene (PP)/ASR composites with robust mechanical performance on a commercial scale. After the SSSM process, the obtained 50/50 wt% PP/ASR composite exhibited a 41.3% increase in tensile strength, 32.9% increase in flexural strength and 55.0% increase in impact toughness when compared with corresponding composites made by traditional direct melt blending. In particular, the toughness of the material can be improved by further addition of PP grafted with maleic anhydride with toughness comparable to that of recycled PP, and a 325% increase in toughness can be obtained with addition of styrene–butadiene–styrene block copolymer grafted with maleic anhydride. This PP/ASR composite shows good processability and high thermal stability, and meets the requirements of many applications for nonstructural products. The approach presented in this paper highlights a novel technique for ASR recycling. © 2018 Society of Chemical Industry     

Mechanical properties and morphology of crosslinked PP/PE blends and PP/PE/propylene–ethylene copolymer blends

Blending is an effective method for improving polymer properties. However, the problem of phase separation often occurs due to incompatibility of homopolymers, which deteriorates the physical properties of polyblends. In this study, isotactic polypropylene was blended with low-density polyethylene. Crosslinking agent and copolymers of propylene and ethylene (either random copolymer or block copolymer) were added to improve the interfacial adhesion of PP/LDPE blends. The tensile strength, heat deflection temperature, and impact strength of these modified PP/PE blends were investigated. The microstructures of polyblends have been studied to interpret the mechanical behavior through dynamic viscoelasticity, wide-angle X-ray diffraction, differential scanning calorimetry, picnometry, and scanning electron microscopy. The properties of crosslinked PP/PE blends were determined by the content of crosslinking agent and processing method. For the material blended by roll, a 2% concentration of peroxide corresponded to a maximum tensile strength and minimum impact strength. However, the mechanical strength of those products blended by extrusion monotonously decreased with increasing peroxide content because of serious degradation. The interfacial adhesion of PP/PE blends could be enhanced by adding random or block copolymer of propylene and ethylene, and the impact strength as well as ductility were greatly improved. Experimental data showed that the impact strength of PP/LDPE/random copolymer ternary blend could reach as high as 33.3 kg · cm/cm; however, its rigidity and tensile strength were inferior to those of PP/LDPE/block copolymer blend.     

Chain structure of polyethylene/polypropylene in‐reactor alloy synthesized in gas phase with spherical Ziegler–Natta catalyst

Two polyethylene/polypropylene (PE/PP) in‐reactor alloy samples were synthesized by multi‐stage gas‐phase polymerization using a spherical Ziegler–Natta catalyst. The alloys show excellent toughness and stiffness. FTIR, ¹³C‐NMR and thermal analysis proved that the alloys are mainly composed of polyethylene, PE‐block‐PP copolymer and polypropylene. There are also a few percent of ethylene‐propylene segmented copolymer with very low crystallinity. The block copolymer fraction accounts for more than 25 % of the alloy. The role of the block copolymer as compatibilizer between PE and PP is believed to be the key factor that results in the excellent toughness–stiffness balance of the material. Copyright © 2004 Society of Chemical Industry     

汽车用薄壁注塑高流动高刚性聚丙烯复合材料的制备及表面优化

该论文为汽车用薄壁注塑高流动性高刚性聚丙烯(PP)复合材料的制备及优化.通过在配方中组合采用高流动抗虎皮纹PP、包覆型滑石粉母粒(解决滑石粉与PP的相容性)、三元共聚PP(解决乙烯-辛烯共混物(POE)与PP的相容性)三种主要材料,以及K树脂、有机硅和其他助剂,再结合薄壁注塑模具在加强筋、卡扣部位的专门设计,结合了材料...     

Improvement of dimensional stability of nylon-6 block copolymer using phenolic resin by reaction injection molding

In order to decrease moisture uptake and hence provide rigidity and dimensional stability in a nylon-6 block copolymer (NBC), powdered phenolic resin was incorporated into the formulation as a filler and processed by reaction injection molding. A novolac resin was cured with hexamethylenetetramine to produce the phenolic resin, which was modified with diethylamine in order to remplaced the  OH groups by diethylamine groups. 5% by weight of modified and unmodified powdered phenolic resin was used as a filler in the nylon-6 block copolymers, and reinforced-nylon-6 block copolymer plaques were produced by reaction injection molding at 145°C. The materials were characterized by dynamic mechanical thermal analysis (DMTA), and their flexural modulus, impact test, and dimensional stability were evaluated. In unmodified phenolic-resin-reinforced nylon-6 block copolymer, water absorption was decreased by 90% compared with the NBC without filler. Two mechanisms of interaction between the NBC and the phenolic resin have been proposed. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 70: 1811–1816, 1998     

单体组成切换法调控聚丙烯/丁烯合金的结构与性能

为解决聚丙烯材料抗冲击强度低的问题,同时利用国内大量廉价的1-丁烯资源,采用单体组成切换法在反应器内进行丙烯本体均聚和丙烯/丁烯本体共聚,原位制备聚丙烯合金。该合金主要由丙丁无规共聚物、长丙烯链段的丙丁嵌段共聚物和高等规度的聚丙烯组成。共聚物作为橡胶相分散在聚丙烯基体中,形成海岛结构,充当应力集中点,起到诱发及终止银纹、吸收能量的作用。长丙烯链段的嵌段共聚物增加了橡胶相与基体的相容性,使合金材料具有优异的刚性和韧性平衡,材料的抗冲击强度最高达48.91 kJ/m²。本文探究了聚合工艺对合金组成结构的影响,并揭示了合金组成结构和相形态、力学性能的关系。     

Studies on the mechanical properties of a glass-fiber reinforced polypropylene/4-(hept-6-enyl)-2,6-di-tert-butylphenol copolymer

The mechanical properties of a short glass-fiber reinforced composite based on a commercial polypropylene grade was compared to a composite system where the bulk material had been replaced by a propylene/4-(hept-6-enyl)-2,6-di-tert-butylphenol copolymer. The mechanical properties of the composites were determined by standard tensile tests. The results indicated that the composite based on the copolymer exhibited a noticeable improvement in tensile properties compared to the composite based on commercial polypropylene. The improved mechanical properties can be attributed to higher wetting of the fibers and to enhanced interfacial adhesion between the fiber and the matrix relative to the composite based on the commercial polypropylene. These assumptions are supported by scanning electron microscopy analysis. © 1993 John Wiley & Sons, Inc.